The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system being developed to meet the growing demand for high speed data services, support ultra-reliability and low latency applications and support massive machine type communication beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE) system.
In order to meet the demand of exponentially increasing data traffic and new services, efforts are being made to develop an improved 5G or the pre-5G communication system. Therefore, the 5G or pre-5G communication system is also called a ‘Beyond 4G Network’ or a ‘Post LTE System’ or ‘Next generation of International Mobile Telecommunication (IMT)-Advanced’ system or IMT-2020 system.
The 5G communication system is considered to be implemented in higher frequency (mmWave) bands (e.g., 10 GHz to 100 GHz bands), so as to accomplish higher data rates. In order to mitigate propagation loss of radio waves and increase transmission distance of the radio waves, a beamforming, massive Multiple-Input Multiple-Output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna, an analog beam forming, large scale antenna techniques are discussed in the 5G communication system.
In addition, in the 5G communication systems, development for the system network improvement is under way based on advanced small cells, cloud Radio Access Networks (RANs), ultra-dense networks, Device-to-Device (D2D) communication, wireless backhaul, moving network based on mobile relay, cooperative communication, Coordinated Multi-Points (CoMP), reception-end interference cancellation and the like.
In the 5G communication system, Hybrid FSK and QAM Modulation (FQAM) and Sliding Window Superposition Coding (SWSC) as an Advanced Coding Modulation (ACM), and Filter Bank Multi Carrier (FBMC), Non-Orthogonal Multiple Access (NOMA), and Sparse Code Multiple Access (SCMA) are potential candidates for advanced access technology.
In addition, the next generation wireless system is expected to address different use cases having quite different requirements in terms of data rate, latency, reliability, mobility etc. However, it is expected that the design of an air-interface of the next generation wireless system is flexible enough to serve a User Equipment's (UEs) having quite different capabilities depending on the use case and market segment the UE cater service to an end customer. Few example use cases the next generation wireless system is expected to address the enhanced Mobile Broadband (eMBB), massive Machine Type Communication (m-MTC), ultra-reliable low latency communication (URLL) etc. The eMBB requirements like tens of Gbps data rate, low latency, high mobility so on and so forth address the market segment representing conventional wireless broadband subscribers needing internet connectivity everywhere, all the time and on the go. The m-MTC requirements like very high connection density, infrequent data transmission, very long battery life, low mobility address so on and so forth address the market segment representing the Internet of Things (IoT)/Internet of Everything (IoE) envisioning connectivity of billions of devices. The URLL requirements like very low latency, very high reliability and variable mobility so on and so forth address the market segment representing the Industrial automation application, vehicle-to-vehicle/vehicle-to-infrastructure communication foreseen as one of the enabler for an autonomous vehicle (e.g., autonomous cars, or the like).
Further, a physical layer of the wireless cellular system in both a Downlink (DL) and an Uplink (UL) operating in mmWave/cmWave would be based on new air-interface different from that of IMT-Advanced air-interface to meet the challenging requirements and provide enhanced mobile broadband user experience. Further, next generation of the IMT-Advanced wireless cellular system is expected to deliver several 100 Mbps to a few tens of Gbps user experienced data rates in comparison to the wireless systems based on the IMT-Advanced. These very high data rates need to be available ubiquitously across the coverage area.
Further, apart from the user experienced data rates next generation of the wireless cellular system is expected to deliver on other requirements like peak data rate (few 10 of Gbps), reduced latency (down to 1 ms), better spectral efficiency compared to the IMT-Advanced system and many other requirements. The next generation of the wireless cellular system is foreseen to be deployed in the higher frequency bands above 6 GHz (e.g., 10 GHz˜100 GHz, also called mmWave and/or cmWave) due to availability of large amount of spectrum bandwidths. In an initial phase of deployment next generation of the wireless cellular system is expected to be deployed in lower frequency bands below 6 GHz using spectrum farming techniques.
Further, one of the requirements for next generation RAT is energy efficiency; so the design of system information provisioning needs to address the energy efficiency requirement to minimize always ON periodic broadcast. Another aspect related to broadcasting of the system information is high signaling overhead in the context of next generation RAT operation in the higher frequency bands (above 6 GHz) where a DL beam sweeping operation is inevitable to reach the coverage area of the cell. Broadcasting all the system information on the coverage beams which are subject to the DL beam sweeping may lead to excessive signaling overhead. Therefore, another design criterion for system information provisioning needs to address the signaling overhead aspect.
Further, another aspect related to broadcasting of the system information using the DL beam sweeping is restrictive and inflexible scheduling. The transmission resources remaining after resources consumed by the system information may be only used for data scheduling for the user in the direction of the DL coverage beam. Therefore, if more time/frequency resources are consumed by the system information then user data scheduling becomes restrictive and inflexible. For the sake of illustration of disclosed methods for acquisition of system information by the UE it is assumed the air-interface of the next generation wireless cellular system would be based on Orthogonal Frequency Division Multiple-access (OFDMA) Radio Access Technology (RAT) in the DL and the UL. However the numerology (i.e. OFDM symbol duration, carrier spacing etc.) of next generation RAT can be different from the OFDMA numerology of the IMT-Advanced system.